> The HY-40R204P has a programmable ARM-Cortex-M3 processor (80KB of available application code space) that developers can use for add-on functions ' development and embed a complete application.

> HY-40R204P can be powered directly with a standard 3V coin cell batteries or a pair of AAA batteries, consuming only 0.15uA in the lowest power shutdown mode and waking up in a few microseconds.

1,> Bluetooth module transmits transparently in slave mode, with single link version and multi-link version.

Single link version: The module can only be connected with a Bluetooth host. Each packet can up to 248 bytes while in the large packet data transmission. Bidirectional rate up to 12K Byte / s, with a 20ms transmission interval.

Multi-link version: The module can be connected with up to 4 Bluetooth hosts. Each packet up to 20 Byte data. 4 channels of transmission interval followed by 20ms / 25ms / 30ms / 35ms.

2,> Single link version and multi-link versions both support bridging mode and direct drive mode. The module will automatically broadcast through the initial settings,then will be scanned and connected by a specific APP. The module can be monitored by BLE protocol after a successful connection.

Bridging mode: The developer can connect the device controlled by a MCU with HY-40R201P Bluetooth module through UART or SPI.Then the module can communicate with the mobile device in two-way. The developer manages certain communication parameters through some specific serial AT commands. The specific meaning of the developer data is defined by the upper application. The mobile device can write to the module via APP, and the written data is sent to the MCU via UART or SPI. When a module receives a packet from the MCU, it automatically forwards the packet to the mobile device. In this mode, the developer only needs to be responsible for the code design of the MCU, as well as the code design of the mobile APP.

Direct drive mode: The developer can carry out a simple external expansion of the module. APP can drive the module directly through the BLE protocol so the module can be monitored and controlled by the intelligent mobile device.
to complete the intelligent mobile device on the module supervision and control.

In this mode, the developer only needs to be responsible for the design of the APP code on the mobile device side. In this mode, the developer only needs to be responsible for the design of the APP code on the mobile device.